It is known that wind may be used for generating electric power by means of wind turbines, also called wind energy systems.
The most common type of wind turbine is the horizontal axis wind turbine, which comprises one or more blades vertically mounted on a rotor hub. When blades are hit by wind, the rotor hub rotates around an horizontal axis and a rotor shaft transmits movement to an electric generator which converts mechanical energy in electric energy.
The rotor hub and the electric generator are placed on the top of a tower which is very tall in order to capture winds stronger than the ones at ground level.
Long conductor wires are used to transport electric energy from the electric generator to the electric grid, or other types of loads such as a battery, which is placed on the bottom of the tower.
While the use of wind turbines is welcome and pushed in order to increase the production of “green” energy, on the other hand wind turbines present several drawbacks.
First of all when there's no wind or when there's too much wind, wind turbines do not work, therefore they just waste the landscape (so called visual pollution). Moreover, when grouped in large wind farms, wind turbines can interfere with terrestrial radio communications (such as television, radio and cell phones) and radar signals.